Ascarid eggs

Ascaris eggs are both a factor of infection and a subject of diagnostics. There are some characteristic features of the appearance of ascaris eggs, as well as some features of their resistance to environmental conditions, which allows this to be taken into account when diagnosing and preventing ascariasis.

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Some features of the appearance of ascaris eggs

Eggs are the very factor by which a person becomes infected. The routes of transmission of roundworm eggs to a person are limited mainly to the fecal-oral mechanism. This is due to the fact that the roundworm is a geohelminth and in the external environment the eggs are preserved in the soil. Therefore, infection occurs with unwashed hands, with poorly processed food, as well as with unwashed vegetables and fruits. Water containing eggs when taken raw can also be a risk factor for the transmission of infection. When it gets into the intestines, the egg is activated and the roundworm development cycle begins.

• What do roundworm eggs look like?

They are small in size - about five to seven micrometers. These eggs are well protected from adverse environmental factors by five membranes. Externally, the eggs are oval in shape, and as for unfertilized ones, the shape can be spherical or round.

The color of the egg shell is brown or dark yellow, which corresponds to the color of the feces. The outer shell is protein, it is not always and under normal conditions it is transparent, but only gets this color from the feces. Next comes the thick three-layer shell, which together with the protein performs a protective function, because the eggs are in the external environment for a long time. The third layer of the ascaris egg wall structure is a lipid layer, which is the thinnest and ensures the exchange of nutrients in the embryo. Then, in the very center, there is the embryo - the blastomere.

If the egg is unfertilized, there is no embryo, only membranes. This structure ensures the stability of the eggs in the external environment. But for the normal development of eggs, optimal conditions are necessary - temperature, soil moisture in which these eggs are stored. The most optimal conditions are soil moisture of about ten ppm, and the temperature of the external environment should be from ten to thirty-five degrees Celsius. At this temperature, the eggs actively grow and larvae are formed already in the human body. Also, to achieve sufficient invasiveness of the eggs, it is necessary that there is a sufficient amount of air and oxygen, because the parasite loves oxygen very much. Therefore, the eggs are stored on the outer covers of the soil and so easily get on food products.

• At what temperature do roundworm eggs die?

Speaking of low temperatures, during the day the eggs die at temperatures below thirty degrees below zero. That is, under the snow cover at a slight frost, the eggs of roundworms can easily survive for months. Roundworm eggs are more sensitive to high temperatures - at the boiling point of water (100 degrees) the eggs die instantly. Therefore, it is important not only to heat the water to a hot state, but to boil it for at least a few seconds - this prevents ascariasis.

It is also important to know that a female can lay up to two hundred thousand eggs at a time, but not all of them are viable, so it is important to detect the pathology in time and not allow it to spread quickly.

Features of diagnostics and treatment of ascaris eggs

Detecting ascaris eggs is a very difficult task. This is due to the small amount of the particle that can be detected in feces, because some of them circulate in the intestine without being excreted. Therefore, for diagnosis, it is sometimes necessary to repeat the tests several times for one positive result.

Ascaris eggs in feces under a microscope have a characteristic appearance - oval shape, thick shell and dark yellow or brown color. Such diagnostics are often difficult, because there may be many unfertilized ascaris eggs, which are difficult to differentiate. Therefore, it is often necessary to use additional diagnostic methods. Light microscopy is used, in which feces are stained with a special luminescent paint and, if eggs are present, they glow under a microscope. It is also possible to determine the presence of eggs and antigen material in feces and other biological fluids (blood) using a polymerase chain reaction.

Ascaris eggs are very often found in children because children have the most contact with sand and unwashed hands. The peculiarity of the course of this pathology in children is the very complex treatment due to the fact that reinfection often occurs due to active games and contact with other children. Therefore, eggs are very often detected in their feces after treatment, which cannot be used as a control for the quality of treatment.

Levamisole (Decaris) is a very common drug for the treatment of helminths. It has a wide range of action, including on roundworms. The drug acts by influencing the muscular layer of the worm wall and disrupting its normal motor activity, which leads to the death of the individual.

• But does Decaris kill roundworm eggs?

Considering the mechanism of action of the drug, it can be said that it is active only against adult worms that are at the stage of intestinal invasion. Therefore, using the drug to treat eggs will not lead to a complete recovery. In this case, it is recommended to use those forms that are active against all forms of existence of roundworms, for example, albendazole.

Ascaris eggs are released by a sick person into the environment and are a factor in the transmission of ascariasis to another person. For high invasiveness of such eggs, optimal conditions for their existence are necessary, therefore, given the sensitivity of eggs to high temperatures, this can be used for prevention. To destroy eggs, it is necessary to select drugs that act on all forms of existence of ascaris - this increases the chance of complete recovery.

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